Abstract:
В работе обсуждается модель процесса имплантационной обработки материалов и результаты модельных расчетов. Модель представляет собой систему нелинейных дифференциальных уравнений и позволяет исследовать динамику структурных превращений в имплантируемом слое в процессе имплантации. Основные процессы, сопутствующие ионной имплантации, введены в модель в виде их вероятностей. Модельные расчеты приводят к экспериментально обоснованным результатам. Модель может быть использована при планировании физических экспериментов по имплантации. The aim of this paper is to investigate the dynamics of the ion-stimulated structural conversions in the implanted layer during implantation treatment. The model and the results of the model calculation are considered in this article. The model is a system of non-linear differential equations. This equations system is obtained on the basis of synergetic approaches. Such basic processes as amorphization, formation of solid solution, crystallisation and sputtering are taken into account in the model. Each of these processes in the given model is presented in the manner of their probability. These probabilities are calculated as functions of the changing parameters of implantation treatment. The considered model permits to calculate the ratio between various phases in an implanted layer under chosen irradiation conditions, or to determine conditions required for obtaining the given phase ratio in the irradiated layer. The model also permits to investigate the dynamics of the structural conversions during nonisotermal irradiation. Some results of calculation of the probabilities of occurrence of the initial crystal phase, amorphous phase, intermediate phase and new crystal phase are presented on drawings. The results obtained do not contradict the experimental data.
It must be noted that although the results for one (B-»Ni) combination are given, model possibilities allow the calculation to be carried out for any combination. Moreover, the calculations are not bound up with some definite way of treatment and, therefore, may be applied in different cases when the surface treatment occurs with bombardment by particles of keV energies. Such parameters of processing as the ion energy, intensity, dose and temperature of irradiation are taken into consideration in the model. These parameters can be easily connected with the technological parameters of different ways of the implantation treatment of materials. These can be the pressure and the ionising degree of gas, the accelerating potential of the part being processed and the time of processing.
